Oil and Gas Producing Activities (Unaudited) - Results of Operations for Oil and Gas Producing Activities (Details) $ in Thousands	4 Months Ended
Apr. 30, 2017 USD ($)
Oil and Gas Exploration and Production Industries Disclosures [Abstract]
Revenues	$ 1,427
Costs and expenses:
Production	(951)
Depreciation, depletion and amortization	(423)
Operating earnings (losses) before income taxes	53
Income tax benefit (expense)	(19)
Operating earnings (losses)	$ 34

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Depreciation, depletion and amortization, and valuation provisions (impairments) related to oil and gas producing activities.

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Income before income taxes for oil and gas producing activities.

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Income tax expense for oil and gas producing activities.

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The results of operations for oil and gas producing activities, excluding corporate overhead and interest costs.

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Production (lifting) costs from oil and gas producing activities, including but not limited to lease operating expense, production and ad valorem taxes, and transportation expense.

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Total revenues from oil and gas producing activities.

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